Donut seat cushion



FIG. 1 is a right front perspective view of a donut seat cushion showing my new design;

FIG. 2 is a left front perspective view thereof;

FIG. 3 is a bottom perspective view thereof;

FIG. 4 is a top view thereof;

FIG. 5 is a bottom view thereof;

FIG. 6 is a rear side elevational view thereof;

FIG. 7 is a front side elevational view thereof;

FIG. 8 is a left side elevational view thereof; and,

FIG. 9 is a right side elevational view thereof.

The broken lines show unclaimed portions of the donut seat cushion only and form no part of the claimed design. 

CLAIM The ornamental design for a donut seat cushion, as shown and described. 